1. Technical Field
This invention relates to the field of wireless telecommunications over a very short distance, called NFC or “Near Field Communication”.
This invention particularly relates to the area of applications hosted in a secure or non-embedded element in a mobile device operating in accordance with NFC standards, particularly the area of contactless transactions carried out with NFC terminals capable of reading electronic tags or cards.
2. Description of the Related Art
Contactless Near Field Communication transmission technology allows communication between a coupler (belonging to the infrastructure) and a mobile wireless communication device or between at least two mobile wireless communication devices. The technology is based on data transmission via the modulation of a magnetic field produced by the coil of a reader (PCD or Proximity Coupling Device) and return data transmission via the modulation of the current induced by coupling in the coil of a card (PICC: Proximity Integrated Circuit Card). Modulation techniques and protocols have for example been described in standards such as standard ISO 14443 or standard ISO 18092.
Devices integrating NFC technology operate in accordance with standard communication protocols, such as for instance ISO 14443, ISO 18092, JIS X6319-4 or proprietary protocols.
Three modes of operating are usually available:                A Reader mode allows reading from and writing on contactless cards and/or contactless electronic tags, also called “smart posters”. For example, that mode allows a user to read information by holding a wireless mobile communication device before electronic tags that may for instance be placed in the street, on posters, on parcels, in bus shelters etc. In this mode, the wireless mobile communication device becomes a reader of passive tags or contactless cards.        A Card emulation mode allows the emulation of a contactless card, that is to say that the wireless mobile communication device associated with a security element, such as of the smart card type, emulates the working of a contactless smart card.        A P2P (Peer to Peer) mode makes it possible to do away with the master role of the reader or the slave role of the card by allowing balanced behaviour (with no master or slave) between two NFC devices.        
A wireless mobile communication device may host several applications that may be in conflict, that is to say they cannot be interfaced with the infrastructure coupler as they use incompatible communication settings.
The NFC wireless mobile communication device is a multi-mode and multi-protocol device.
An application is defined by a mode and protocol configuration. In general, the wireless mobile communication device may include different applications such as reader type applications, card emulation type applications or others. For reader applications, the wireless mobile communication device is in reader mode to read from or write on a remote device through contactless technology. The wireless mobile communication device is in this case used as an RFID reader. For card emulation type applications, the NFC wireless mobile communication device is in card emulation mode so as to be read by conventional couplers in payment or paid-for access control applications (payment machine, transport network entrance etc.). The wireless mobile communication device, for example a mobile telephone, is then used like a smart card. The application program is for instance held and executed by a secure processor, and access to the service requires identification of the subscriber. A permissive card reader may according to the standards quoted above accept all cards regardless of their parameters.
However, with the current NFC standards, those parameters are not only necessary for establishing a connection to carry the application data and commands. Some parameters contain application data that no longer allow generic setting up independently from the applications. Parameters that do not contain application data are sometimes tested by the reader. The reader may then reject the card altogether when the parameters shown by the card are not strictly and uniquely those that are expected by the reader. That may sometimes lead to conflicts between applications that cannot share the same NFC connection parameters.
A solution concerning the cohabitation of several applications using the card emulation mode may for instance consist in using an algorithm according to which each application is sent to the terminal with all its NFC parameters and two masks A and B. Mask A applied to the parameters provides information about the data that are required and expected by the reader. Mask B applied to the parameters provides information about the data that are not tested by the reader. According to this algorithm, two applications do not conflict with each other if the merging of their parameters (logical AND) does not contain differences (exclusive OR) in respect of the parameters expected by the readers and/or if there are differences, they relate to data that are not expected by the readers.
With this solution, the user of the mobile device has the means to detect applications with conflicts and to preselect the applications that can cohabit in order to carry out the transaction rapidly without requiring any intervention by the user, particularly at a stage where time is critical, for example in applications relating to the transport of users.
However, this solution is not entirely satisfactory. That is because the user may need to activate an application in conflict with a group of applications with no conflict. Further, some applications such as banking applications are exclusive of each other, even if they are not in conflict. As a result, for such applications, the user must know exactly with which bank account they will pay their transaction. That leads to repeated switching, which is neither ergonomic or desirable, of the preselection of applications, which can lead to the depreciation of NFC technology in use.
In order to correct those drawbacks, one of the aims of this invention is to offer a simple means to preselect one or more applications that can share the same parameters relating to NFC technology.